In the past, push-button dials in telephones have used a mechanical key pad with sequential metallic switching to perform state transformations. When operating the push-button dial, the operation of any key on the dialing pad operated a plurality of metallic contacts in sequence as the button was depressed. The first set of contacts to be closed inserted a resistor in series with the receiver to mute the receiver. This was followed by the operation of a second set of metallic contacts which opened the transmitter path to limit outside noise interference. Full depression of the key finally closed a set of contacts for inserting the dial tone circuit into the line to produce the dial tone signal associated with the key. The reverse sequence occured when a key on the key pad is released. When operating in the speaker phone mode, a metallic set of contacts is required to removed the shunting effect of the hybrid network and provide a speech path to the speaker phone. When a push-button is depressed, a set of metallic contacts inserted a resistor to mute the audio signals and an additional set of metallic contacts inserted the dial tone generating circuit. Such push-button dials are expensive and difficult to manufacture in large numbers while maintaining the required quality. The contacts must be arranged to carefully control the sequence in which the multiple sets of contacts open and close.